"Do you think people who want to be useful should get a PhD?" "Umm... Mostly not."
"Sometimes it [technology] gets worse... In '69 we were able to go to the moon.. Then the space shuttle could only take people to LEO, then the space shuttle retired... That trends to zero. People think technology automatically gets better every year but it actually doesn't, it gets better if smart people work like crazy to make it better... By itself if people don't work on it technology will decline. We look at Rome and how they were able to build these incredible roadways and aqueducts and indoor plumbing, and they forgot how to do all of those things.
Entropy is not on your side."
"I know a lot of people think I must spend a lot of time doing media and business-y things... But 80% of my time is spent on engineering and design."
"A very long time ago you took me on a tour of SpaceX. And the most impressive thing was that you knew every detail of the rocket and every pieces of engineering that went into it and I don't think many people get that about you."
"What really matters is the machine that builds the machine, the factory. That is at least 2 orders of magnitude harder than the vehicle itself."